MILLIONS of Britons could avoid the misery of arthritis by losing just a few pounds in weight, scientists have discovered.

By shedding less than a stone, overweight people could cut their risk of developing the debilitating condition by a quarter.

Osteoarthritis affects an estimated 8.5million Britons.

And, according to Arthritis Research UK, the NHS spends £5.2billion a year treating the condition and replacing at least 77,000 knees and 66,000 hips.

But now Dutch researchers have discovered how eating more healthily and taking modest exercise can help overweight people to spare their joints the wear and tear that leads to the condition. Scientists at the Erasmus Medical Centre in Rotterdam recruited 407 women aged between 50 and 60.

Although none had osteoarthritis, they were all overweight with a body mass index of 27 or higher.

A healthy BMI score is anything between 18.5 and 24.9.

Half the women were put on a programme of healthy eating and regular exercise while the others were told to carry on with their normal diet and lifestyle.

The researchers tracked the women for more than two years and found that 20 per cent of those in the “unhealthy” group went on to develop osteo-arthritis in a knee. But in the group which adopted a healthy lifestyle, the figure was only 15 per cent.

Further research showed the benefits kicked in after the women had ditched just 11lbs of their excess weight.

The results are due to be published later this year.

Dr Jos Runhaar, who led the research, said: “Doctors and physiotherapists can use these results to encourage patients to change their lifestyle.”

British experts last night welcomed the findings.

Professor Alan Silman, medical director of Arthritis Research UK, said: “This chimes very much with our research, which shows that compared with someone of normal weight, an obese person is 14 times more likely to develop knee osteoarthritis.

“Losing weight, however modest, when combined with exercise, is a panacea at every stage.”

Osteoarthritis is caused by the destruction of cartilage, the body’s built-in shock absorber.

Cartilage soaks up the impact from walking, running or lifting, so that bones do not rub together and disintegrate.

But in osteoarthritis, the cartilage starts to break down and, as bones come into contact, the friction makes joints swollen and extremely painful.

Currently one in five people over the age of 45 has osteoarthritis in a knee.

But with ageing and obesity among the most common contributors to the condition, the number of people in Britain consulting a GP about knee osteoarthritis alone could rise from 4.7 million in 2010 to 8.3million by 2035.

There is no cure or effective treatment for the condition other than pain relief, which is often inadequate, or joint replacement.

Losing just 11lbs slashes danger of arthritis [ALAMY]

Osteoarthritis affects an estimated 8.5million Britons

More extreme measures include steroid injections, to dampen down inflammation.

According to Dr Silman, “once osteoarthritis has developed in one knee, the risk of getting it in the other one increase five-fold”.

He added: “The danger to health and quality of life of obesity is insidious.

“At every stage, excess body weight increases the level of pain and disability and undermines the efficacy of treatment for osteoarthritis. And whereas high blood pressure and diabetes – other examples of obesity-related health – may be substantially improved on losing weight and are relatively easy to control with therapy, osteoarthritis is irreversible.

“But achieving a healthy weight reduces the risk of developing the disease in the first place, relieves existing symptoms and helps to prevent further deterioration.”

An American study at Wake Forest University in North Carolina found strict dieting and moderate exercise slashed knee pain in osteoarthritis sufferers by half.

Researchers studied 454 patients who dieted for 18 months with the aim of losing at least 10 per cent of their body weight.

They concluded that this combination of controlling eating habits and keeping mobile was “potentially one of the best treatments” for knee pain.